Year US Dollars 1966 -3274682.19746 1967 -3113823.35313 1968 -4528872.46196 1969 -4832525.32041 1970 -1630250.084 1971 -2682809.30595 1972 -4131064.80787 1973 -5472509.3985 1974 -4543164.41639 1975 1260066.37168 1976 -5943837.8937 1977 -14888791.97558 1978 -45032842.6907 1979 -58604374.07329 1980 -50294886.69378 1981 -49869410.10954 1982 -33064031.44791 1983 -25600697.3395 1984 -24232024.77609 1985 -22689334.60027 1986 -17588433.213 1987 -21773224.58442 1988 -21567363.30571 1989 -29029748.40445 1990 -37035156.74578 1991 -36069665.98344 1992 -44695751.88012 1993 -62259984.20082 1994 -55515414.64026 1995 -92162075.79393 1996 -62405238.23133 1997 -19713809.53315 1998 -27391727.97399 1999 -29481382.34855 2000 -37286120.92965 2001 -22599711.867 2002 -30809466.909 2003 -32491431.97631 2004 -84115604.01064 2005 -104950411.89275 2006 -87544582.88943 2007 -105293204.78905 2008 -158342495.62913 2009 -149149539.86579 2010 -180208482.07911 2011 -131222103.42311 2012 -122174386.08852 2013 -105540970.47634 2014 -160736108.11588 2015 -233471778.48533 2016 -182501238.90671 2017 -194453569.21227